Slightly generalized Generalized Contagion: Unifying simple models of biological and social spreading

TL;DR

This paper introduces a unified generalized contagion model that captures biological and social spreading processes by emphasizing system memory, covering simple, critical mass, and explosive contagion dynamics.

Contribution

It proposes a comprehensive framework that unifies various contagion models, highlighting the role of system memory across different spreading phenomena.

Findings

Unified model encompasses biological and social contagion

Identifies conditions for global spreading from small seeds

Classifies contagion into three main types

Abstract

We motivate and explore the basic features of generalized contagion, a model mechanism that unifies fundamental models of biological and social contagion. Generalized contagion builds on the elementary observation that spreading and contagion of all kinds involve some form of system memory. We discuss the three main classes of systems that generalized contagion affords, resembling: simple biological contagion; critical mass contagion of social phenomena; and an intermediate, and explosive, vanishing critical mass contagion. We also present a simple explanation of the global spreading condition in the context of a small seed of infected individuals.